Cooling transformers



y `UNITED STATES PATENT OFFICE.

- ELII-IU THOMSON, OF SWAMPSCOTT, MASSACHUSETTS, ASSIGNOR TO THE THOMSON-HOUSTON ELECTRIC COMPANY, OF CONNECTICUT.

CooLlNe TRANsFoRMERs.

SPECIFICATION forming part of Letters Patent No. 508,654, dated November 14, 1893.

Application filed February 4, 1892. Serial No. 420,341, (No model.) I

prevent excessive heating, especially whenv the station is kept in operation during the entlre day as is often the case. The highest efficiency 1s obtained with `a transformer when the conductors under load are cold.v

Il [eating impairs its efficiency and also lessens its durability, especially if permitted to become considerable. Furthermore the insulating qualities of the insulating materials used in the transformer are much less at high temperatures, and even oil itself is not so good an insulator when hot. It is therefore the design of this invention to preserve the transformer comparatively cool, thus securing the advantages indicated, and this I accomplish by exposing oil or other insulating duid in which the transformer is immersed to some special articial cooling medium which may be passed through the oil, or through which the oil itself may be circulated as hereinafter more particularly set forth.

Heretofore it has been customary to immerse transformers in oil contained within a `metal casing, whereby heat is conducted and face is obtainable to prevent overheating.4

For such installations as these it is specially desirable to provide an artificial cooling medlum as contemplated in the present invention.

In the drawings Figures 1 and 2 are sectional views, showing two ways in which the desired cooling may be effected, but it will be understood that other dispositions may be employed as may prove most convenient in any given'case.

In the first of the arrangements, illustrated in Fig. 1, the upper and lower portions of the receptacle containing the transformers are connected by an external pipe or pipes, and the cooling medium being applied to a greater or less portion of said pipe causes a constant circulation of the fluid through the chamber, and around the transformers preserving them cool. For illustration the transformer station is'shown located in an underground chamber A, walled in with suitable masonry, and provided with a man-hole and cover L permitting ready access thereto. Within the chamber are arranged any desired number of transformers T, supported on insulating blocks B, and immersed in an insulating uid C, preferably oil. A pipe or system of pipes P, P', which may be more or less extended as may prove convenient, is provided forming a passageway connecting the upper portion of the chamber with its lower portion, and this pipe is filled with oil as well as the transformer receptacle. A greater or less portion of this pipe system is exposed to a cooling medium, which of course cools the oil in its immediate neighborhood, and gives rise to a continuous circulation throughout the casing, inasmuch as the iiuid in becoming heated tends to rise passing out at the upper end of the pipe, and being replaced by cooler material ventering at the other end. In Fig. l a pipe W, which may be part of a city water system, contains the cooling medium, and the pipeP is expanded into a casing surrounding it as shown. In actual practice it would be better to arrange the cylinder D at a higher level than is illustrated, say around the pipe P, so that the oil or other Huid cooled in the cylinder may fall therefrom through the pipe P', being replaced by heated oil coming through pipe P.

In the arrangement shown in Fig. 2 the cooling medium is introduced directly inside the transformer casing and passed through the oil therein. Here K represents the casing containing the transformer, filled with an insulating fluid as before. Through the pipes P,

P is passed a onrrentof cold Water or other 2. The combination with a receptacle concooling fluid. This will abstract the heat taining one or more transformers surronndfrom the interior of the casing and keep the ed by an insulating Huid, of a pipe passing x5 apparatus in good Working condition. through said chamber and fluid, and means 5 That I claim as new, and desire to secure for causinga cooling medium to iiow through by Letters Patent, ism said pipe, substantially as described.

l. The combination of a receptacle orcham- In witness whereof I have hereunto set my ber containing one or more transformers snrhand this 29th day of January, 1892. rounded by oil or like insulating fluid, with a ELII-IU THOMSON. 1o cooling medium circulating in a pipe passing Vitnesscs:

through a greater or less portion of the fluid, JOHN WV. GIBBONEY,

as set forth.

BENJaMIN B. HULL. 

